Fix: Controller inputs bound to a modifier key combination would not be triggered if additional modifier keys were also pressed.

Author: SuuperW

src/BizHawk.Client.Common/input/InputCoalescerControllers.cs

@@ -11,14 +11,16 @@ public class InputCoalescer : SimpleController
 		public InputCoalescer()
 			: base(NullController.Instance.Definition) {} // is Definition ever read on these subclasses? --yoshi
 
-		protected virtual void ProcessSubsets(string button, bool state) {}
+		protected virtual void ProcessInput(string button, bool state)
+		{
+			Buttons[button] = state;
+		}
 
 		public void Receive(InputEvent ie)
 		{
 			var state = ie.EventType is InputEventType.Press;
 			var button = ie.LogicalButton.ToString();
-			Buttons[button] = state;
-			ProcessSubsets(button, state);
+			ProcessInput(button, state);
 			if (state) return;
 			// when a button or modifier key is released, all modified key variants with it are released as well
 			foreach (var k in Buttons.Keys.Where(k =>
@@ -30,10 +32,21 @@ public void Receive(InputEvent ie)
 
 	public sealed class ControllerInputCoalescer : InputCoalescer
 	{
-		protected override void ProcessSubsets(string button, bool state)
+		protected override void ProcessInput(string button, bool state)
 		{
 			// For controller input, we want Shift+X to register as both Shift and X (for Keyboard controllers)
 			foreach (var s in button.Split('+')) Buttons[s] = state;
 		}
+
+		public override bool IsPressed(string button)
+		{
+			// Since we split all inputs into their separate physical buttons, we need to check combinations here.
+			bool allPressed = true;
+			foreach (var individualButton in button.Split('+'))
+			{
+				allPressed &= Buttons.GetValueOrDefault(individualButton);
+			}
+			return allPressed;
+		}
 	}
 }